Google has geotargeting enabled for everyone searching on google.
What does Geotargeting mean?
1. Potential customers/clients might search for a "dentist" and not type in "phoenix" however google knows that they are in phoenix so google provides search results as if you typed in "dentist in phoenix."
For local search terms, always use the keyword + city. In some cases, there are multiple cities with the same name in different states. In that instance, monitor keyword + city + state, spell the state out or use initials.